1. Field of the Invention
This invention relates to a high-energy laser (HALE) and especially to a HALE consisting of a plurality of lower-power lasers forming a large loop, the outputs of each individual laser remaining in phase with the output of the large loop.
2. Description of the Prior Art
In the process of directing laser energy against a remote target to destroy or damage it, a large amount of coherent laser energy must inpinge on the target. The intensity of the laser beams at the target increases with the laser power and with the area of the telescope aperture (telescopes are generally used in this type of laser application). There are practical limits to the size of both the laser and the telescope that can be constructed with the optical precision and power-handling capabilities that are required. Thus, it would be highly desirable to operate with several smaller lasers (less power) and smaller telescopes directed separately at the same target. This requires that the outputs from the various lasers be locked in frequency and phase and that the path lengths from the lasers to the targets be controlled in order for the beams to combine coherently at the target to provide the higher power which is required and desired.